義ぎ甲こうぎこうMeanings1nounplectrum; pickrare termRare term for a plectrum used with stringed instruments such as the shamisen or biwa. More commonly called 撥 (ばち).義ぎ甲こうは、三味線しゃみせんや琵び琶わなどの弦げん楽がっ器きで使つかわれる道どう具ぐです。A 義甲 is a tool used with stringed instruments like the shamisen or biwa.